Add a specified node to a geometry node group. Define its position in the node editor to build or modify procedural geometry trees.
Add a node to a geometry node tree.
Args: node_group_name: Node group name. node_type: Node type (e.g., 'MeshPrimitiveCube', 'InstanceOnPoints', 'SetPosition'). location: [x, y] position in the node editor.
| Name | Required | Description | Default |
|---|---|---|---|
| location | No | ||
| node_type | Yes | ||
| node_group_name | Yes |
Changes observed during successful MCP inspections.
v3.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden of behavioral disclosure. It states the core mutation (adding a node) but does not mention prerequisites (e.g., whether node_group_name must already exist), side effects like automatic connections, or return values.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is short and front-loaded with the core purpose. The Args block is a bit redundant with the schema, but it is structured and free of fluff.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a simple 3-parameter tool, the description covers the basic invocation, but omits important operational context such as whether the node group must already exist, what happens when location is absent, and what is returned. It is minimally viable but not complete.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0%, so the description must document parameters. It names all three parameters and adds useful examples for node_type (e.g., 'MeshPrimitiveCube') and specifies location format as [x, y]. However, node_group_name is only repeated as 'Node group name' with no additional context.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a clear action and resource: 'Add a node to a geometry node tree.' This distinguishes it from sibling tools like add_geometry_nodes_modifier and connect_geometry_nodes, though it does not explicitly call out the difference.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
No guidance is provided about when to use this tool versus alternatives such as connect_geometry_nodes or add_geometry_nodes_modifier. The intended context is only implied by the tool name and description.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.